What is the default match of other pendant?
This problem arises when in the nested if statement, the number of ifs is greater than the number of else clauses. One way to override the default matching of else statements is to put the last unmatched if that occurs in a compound statement.
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Which of the following statements creates the problem of the other pending?
The pending else problem often occurs when there is an if statement without the presence of a true or false statement. A switch statement without a default value does not cause the problem of something else pending. This problem mainly arises due to nested if statements.
How else can pendants be removed?
The dangling problem else in the construct If (E) sales S | is (E)S | a can be resolved IN SDTS (A) using associative precedence of operate and the munch ‘exe’ principle (B) Changing the grammar to an unambiguous one (C) Cannot be deleted because it is undecidable (D) None of the above dangling problem else…
How to resolve pending else ambiguity in C++?
Java, C, and C++ have chosen to resolve the Dangling-Else ambiguity using the following rule: an else keyword is always associated with the closest preceding if keyword that does NOT cause a syntax error.
What is another outstanding problem with the example?
The dangling else is a problem in computer programming in which an optional else clause in an if-then(-else) statement results in nested conditionals being ambiguous. Formally, the reference-context-free grammar of the language is ambiguous, meaning that there is more than one correct parse tree.
Does factoring to the left remove ambiguity?
2 answers. In the case of the dangling else, the ambiguity is not removed by left factoring. You will still have two parse trees for nested if statements.
What is a hanging statement?
A dangling modifier is a word or phrase that modifies a word that is not clearly stated in the sentence. A modifier describes, clarifies, or gives more detail about a concept. Having finished her homework, Jill turned on the television. “Having finished her” she declares an action but she does not name the author of that action.
What causes one other thing to hang?
What is disambiguation?
A grammar is said to be ambiguous if it can produce more than one parse tree for a particular sentence; this occurs when two different sequences of leftmost (or rightmost) derivations can produce the same sentence from the same start symbol.
How do I fix hanging over issues?
The problem can also be solved by making the link between an else and its if explicit within the syntax. This generally helps prevent human error. Possible solutions are: Have an “end if” statement.
Why do we eliminate left recursion?
Eliminating Left Recursion Left recursion often poses problems for parsers, either because it leads to infinite recursion (as is the case with most top-down parsers) or because they expect rules in a normal form that prohibit it (as is the case with many parsers). bottom-up parsers, including the CYK algorithm).
What is an example of the dangling something else problem?
Hanging else is a problem that occurs when we use nested if. For example: if(condition) if(condition-1) if(condition-2) else Statement; Here in the example above, we actually want to give the else clause to the outermost if condition, but it is considered for the innermost if condition. This is called the dangling else problem.
How to avoid human error when hanging something else?
Alternatively, one can rely on a non-context-free grammar or a parsing expression grammar. The problem can also be solved by making the link between an else and its if explicit within the syntax. This generally helps prevent human error. Possible solutions are: Have an “end if” statement.
How to avoid hanging something else or if another ambiguity?
The following syntax requires that the next else be matched with the most recent unmatched if, which disambiguates if-else. We define an open statement as one that has at least one if that is not paired with an else within the statement.
Can a statement be closed between an if and an else?
In this syntax, we only allow closed statements between an if and its matching else. In other words, between an if and an else, an if is only allowed if it is combined with a matching else clause. The net effect is that each else is associated with the closest previous if.